The Incorporated Trades were given seals of cause by the town council, which were effectively their founding charters, although several of the crafts existed as coherent bodies some years before the dates of their earliest-known seals of cause.
The document of a seal of cause gets its name from the wording round the border of the seal appended to it: “S.[IGILLUM] COMMUNITATIS. BURGI. DE EDENBURGH. AD. CAUSAS.”; this distinguishes such documents from all other acts of council which, if sealed at all, bore the ordinary common seal of the burgh. In addition, the words “seal of cause” are usually included by the clerk in the wording of the document. The text usually consists of the granting of rights and privileges and the imposition of responsibilities.
The town council also issued supplementary seals of cause containing additional provisions. If an original became lost or destroyed, the council would sometimes issue a replacement.
Seal appended by the City of Edinburgh to its seals of cause.